The Propagation of Pomegranates
By Ashley Braun
In my paper I’m going to
explain to you what a pomegranate is and its care. I will also go in depth on the different methods of propagating
pomegranates. Pomegranates are not
widely grown in the United States mostly because of unfavorable climate, but
also because the demand for pomegranates is not very high in the United
States. This lack of interest created a
small problem with finding strong research information about the pomegranates
propagation. There are several
different propagation methods used to grow pomegranates. Much work needs to be done to increase
production and information about the pomegranate, but the field and interest in
the rare fruit is growing and has the potential to double within the next ten
years.
The pomegranate is native to
the Middle East and South Asia. It has
wandered over the centuries to China, India, the Mediterranean, California, and
Florida. The pomegranate is one of the
first five cultivated foods in the world.
There are some trees in Europe that are known to be over 200 years
old. Throughout the centuries it has
been used widely in literature and art and was often seen as a sign of
fertility or wealth. The pomegranate is
very high in potassium, vitamin C, and antioxidants.
The pomegranate plant comes in either a tree or a
shrub. It is usually grown for its
large fruit, but there are some dwarf cultivars used primarily for landscaping
or bonsai trees. The foliage is long,
thin, and glossy in appearance. It
produces small flowers usually one inch in diameter. The flowers come in a wide variety of colors, but the most common
are orange and red. The fruit produced
is usually two to five inches in diameter with a hard rind. The rind comes in many different colors from
green, yellow, orange, and red. Inside
the fruit are locules separated by a thin, bitter membrane.
Within the locules are many small jewel-like objects called arils. The arils contain tart to sweet flavored
juice and a small seed. The juice
ranges in color from clear to a deep staining red.
The pomegranate is capable
of growing in a wide range of soils as long as it has good drainage. It
likes to be placed in an area with a lot of sunlight. You should plant the tree or shrub in early spring with rows 15
to 18 feet apart, but make sure to protect it from any late frosts that come
along. Every spring you may also add a
couple inches of mulch around the base of the tree or shrub. The pomegranate is tolerant of drought, but
only cold hardy till 12 degrees Fahrenheit.
It prefers very warm temperatures, which improve the flavor of the
fruit. For mass fruit production
sprinkler irrigation is preferred, but should not be utilized close to harvest
time because it causes fruit cracking.
The pomegranate is self-pollinating, or it can be cross-pollinated by
insects. Cross-pollination also
increases fruit set and quality. The
plant requires very little fertilizer, around 5-8 ounces of nitrogen a
year. Minor pruning is needed, but
necessary to decrease disease and increase fruit size. You must also remember to remove the suckers
from the base of the plant.
The fruit takes five to
seven months to mature after it blossoms.
The fruits are usually harvested September to December. Almost all harvesting is done by hand. After being picked they should be kept at
optimal conditions of 32 to 41 degrees Fahrenheit and 80 to 85% relative
humidity. Pomegranates can be kept that
long for up to seven months. The long
storage improves the flavor of the fruit.
An easy method of
propagation is to do it by seed. The
seeds of the pomegranate germinate very quickly, even if sprinkled on the top
of the soil. They usually have little
problem with dormancy since the tree is native to warm climates. Seeds are also more economical than other
methods of propagation. The biggest
problem with seed propagation is that they are not true to type, and can loose
some of the good qualities of the established cultivars. That is why the seed propagation is not used
in large-scale production. It also
takes longer for a fruit producing plant to grow from seed than other
methods.
Hardwood cuttings are the
most widely used method. You should
take the cuttings November through January off of one-year-old wood. One source said the cuttings should be six
to ten inches long while another source suggested cuttings of twelve to twenty
inches in length. Treat the cuttings
with a growth regulator and let them develop some roots in a greenhouse before
planting in the spring. The cuttings
are the best way to keep the properties of the original cultivars.
Grafting of pomegranate trees is rarely done in the
United States. It is sparsely used in
other parts of the world. Many
different types of grafts have not been successful enough for use in commercial
production. I have not found much
information explaining why there is such difficulty getting successful
grafts.
Tissue culture is another method
of production that calls for the growth of the plant in a sterile environment
using the tissue, seed, or cuttings.
There is little, if almost no tissue culture of pomegranates. The United States has such a small pomegranate market that very
little money is put into its research and the expense of tissue culture. Many of the countries that have large
pomegranate production have poor economical status and cannot provide much
money to its research.
I would have liked to find more
specific information on the propagation of pomegranates. Since the fruit has been grown for hundreds
of years with reliable results there is not much want for growers to explore
other options. The minimal U.S.
production posed a problem in finding information also. It was very easy to find general production
knowledge and facts, but in depth statistical information is very hard to come
by. The propagation of pomegranates has
been done for many years and the plant has endured.
California Rare Fruit
Growers. “Pomegranates.” June 4, 1997.
<http://www.crfg.org/pubs/ff/pomegranate.html>.
Corbis Photo Search.
“Pomegranate.” April 26, 2003. <http://www.corbis.com>.
Gernot Katzer’s Spice
Dictionary. “Pomegranates.” February 27, 2000.
<http://www-ang.kfunigraz.ac.at/~katzer/engl/generic_frame.html?
Puni_gra.html>.
POM Wonderful. July 14,
2001. <http://www.pomwonderful.com/home.asp>.
Pomegranate. March 24, 1999.
<http://www.hort.purdue.edu/newcrop/morton
/pomegranate.html>.
Virginia Cooperative
Extension. “Pomegranates.” November 1, 1997.
<http://www.ext.vt.edu/departments/envirohort/factsheets3/fruithome/NOV90PR3.HTML>.